AimatraLab Alloy Builder

Supports 2–2048 fully periodic sites, 2–8 target elements and up to five shells, each with uniform nonzero coordination. Positive ratios become integer populations through Hamilton largest remainders; inspect actual composition. The HCP template is a close-packed atomic lattice.

SCRAPs exposes population, MC and global/local search budgets, seed and shell weights. Sublattice mode exposes sampling budget, seed, shells and weights, with a default distance-clustering tolerance of 0.03 Å. Larger budgets do not guarantee zero error or a fixed runtime. Both methods use one serial native worker.

Sublattice import rejects partial/mixed occupancy, disorder and ambiguous CIFs; Selective Dynamics constraints are unsupported. Native sqsgenerator adjacency must match the full periodic-image graph. Unrepresentable repeated-image bonds or self images are rejected; fewer shells or an explicitly enlarged cell may be required.

Strict V2 checks may conservatively reject some equivalent lattice-wrap representations at exact boundary coordinates. These checks were not weakened; arbitrary CIF input is not guaranteed to succeed.

The two methods use different objective functions, so their values are not directly comparable. Signed SRO is retained; finite cells may not reach zero. A validation badge records structural and numerical consistency checks; same-seed reproducibility is scoped to the same implementation and environment.

Ball-stick, spheres, wireframe and coordination polyhedra; a/b/c or custom [uvw] views, display repetition, element visibility and colours/radii, labels and cell/axis controls, a larger window, and PNG / TIFF image export (transparent backgrounds for PNG only).

Display copies, distance-based links and convex polyhedra affect the view only. They do not change the scientific structure, composition or export, or validate chemical coordination or energy.

The application uses a modified serial SCRAPs derivative; no endorsement by the original authors or institutions is implied. Both backends retain their method and license attribution.

1. SCRAPs / Hybrid-Cuckoo-Search
2. Singh et al. Accelerating computational modeling and design of high-entropy alloys. Nature Computational Science 1, 54–61 (2021). DOI: 10.1038/s43588-020-00006-7
3. sqsgenerator: official SRO and objective definitions